In recent years, many children in their early age are taught to learn musical instruments for better emotional development. Some electronic musical instruments have a lesson function for performance of a musical piece. However, children, whose fingers and intelligence are still at an early stage of development, often mishandle such electronic musical instruments, in such a way as banging an electronic keyboard, instead of playing the instruments properly.
On the other hand, electronic musical instruments, such as an electronic keyboard, are made for the purpose of performing music, and naturally produce a tone at a pitch corresponding to each key.
PATENT LITERATURE 1: Jpn. Pat. Appln. KOKAI Publication No. 2007-286087
Accordingly, a conventional keyboard produces pitches corresponding to a plurality of pressed keys, even when such keys are hit randomly. Even when a chord is intended to be played, no musically correct chord is produced since keys are hit randomly, and a random dissonance is produced.
How to play instruments properly and correct chords can be learned with an instructor. However, without an instructor, there has been a problem that children gradually become bored with a musical instrument without knowing how to perform properly, and lose interest in a musical instrument itself.